The line driver integrated circuit (IC) and bidirectional transceiver IC have been widely used in the field of electronic equipments. The line driver acts as a buffer and provides driving power in the electronic circuit. The bidirectional transceiver play the same role as the line driver. The major difference between them is the direction of the data transmission. While the line driver provides only one direction data transmission, the bidirectional transceiver provides bidirectional data transmission.
In FIG. 1, a typical line driver circuit having 8 input lines and 8 output lines is shown. In FIG. 2, a typical bidirectional transceiver having 8 bidirectional data lines is shown.
It is known both circuits have common mask layout with the exception of some proprietary mask layouts for the bidirectional transceiver. Therefore some IC manufactures by adopting IC manufacturing processes known as metal option or buried-N option produce selectively the line driver and the bidirectional transceiver with same set of mask layouts. In other words, the line driver is produced by the same set of mask layouts as those used in producing the bidirectional transceiver except the metal or buried-N mask. This kind of approach obviously reduces the cost of manufacturing the line driver or bidirectional transceiver compared to the conventional approach, not to mention other merits.
The instant invention provides a different approach to selectively produce the line driver or the bidirectional transceiver with same set of mask by a bonding option approach.
By selectively bonding or not bonding a pad corresponding to a selection signal of an integrated circuit of the instant invention, the line driver function or bidirectional transceiver function may be selectively determined by the invention.